Audubon has started a new website -- www.hummingbirdsathome.org -- to help gather information about them. Anyone with a feeder and some sugar water or a stand of bee balm can help.

What Audubon is asking people to do is register on the website, identify a patch of ground where they see hummingbirds regularly -- a yard, a park, a public garden -- then report on what they see.

They want to know what hummingbird people see and on what flowers. Like all citizen-science projects, this one will last for years.

"The project is designed for people to collect data while they're out in their yard and garden," said Kathy Dale, director of citizen science for the National Audubon Society.

One of the issues the Audubon Society wants to learn about is whether the environment and hummingbirds are out of synch.

Hummingbirds are migrants who winter in the tropics, then fly north in the spring to breed and nest.

But because of climate change, some of the flowers -- and their nectar that hummingbirds feed on -- may be blossoming earlier than they have in the past. Audubon wants to know if this is happening and how it may affect the health of the species.

Hummingbirds at Home will run through mid-June. Dale said people can file reports as often as they want. The more the better. There is an app to let people send in data from their smartphones.

"People can send data from outside," Dale said.

In Connecticut, pickings are slimmer than in the West and Southwest. There is only one species -- the ruby-throated hummingbird -- that we see with any regularity.

Patrick Comins, director of bird conservation for Audubon Connecticut, said ruby-throated hummingbird numbers are increasing in the state.

But studying them here is important, he said.

"They are a tropical migrant that has to travel long distances to get here," Comins said. "We want a robust population that can withstand anything that might happen to it."

Getting to watch hummingbirds -- and who wouldn't like to do that? -- is important in another way.